Heavy metal retention in copper mine soil treated with mussel shells: Batch and column experiments

• Published in: Journal of hazardous materials Vol. 248-249; pp. 122 - 130
• Main Authors: Ramírez-Pérez, A.M., Paradelo, M., Nóvoa-Muñoz, J.C., Arias-Estévez, M., Fernández-Sanjurjo, M.J., Álvarez-Rodríguez, E., Núñez-Delgado, A.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.03.2013
• Subjects: Adsorption; Animals; Environmental Restoration and Remediation - methods; Heavy metals retention; Industrial Waste; Laboratory columns; Metals, Heavy - analysis; Metals, Heavy - chemistry; Mine soil; Mining; Mussel shell; Mytilus; Soil Pollutants - analysis; Soil Pollutants - chemistry; Transport experiments; Transport experiments; Adsorption; Mine soil; Laboratory columns; Heavy metals retention; Mussel shell
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2012.12.045

► Mussel shell amendment on mine soil raises pH proportionally to the shell dose used. ► Shell amendment clearly increased Cu, Cd, Ni and Zn retention in soil/shell mixtures. ► Retention decreases when increasing amounts of metal are added to un-amended soil. ► Shell amendment would favour remediation and restoration of contaminated acid soils. Batch and column experiments are used to study the effects of ground mussel shell amendment on the retention of heavy metals in acidic mine soil. The soil pH increases proportionally with the mussel shell concentration employed. Mussel shell amendment increases Cu, Cd, Ni and Zn retention in mine soil when compared with unamended soil. In fact, Cu retention was 6480μmolkg−1 (43% of the total added) when the maximum metal concentration (1570μM) was added to the unamended soil, whereas retention reached 15,039μmolkg−1 (99.9% of the total Cu added) when soil was amended with 24gkg−1 mussel shell; in the case of Cd, adsorption increases from 3257μmolkg−1 (15% of the total added) for the unamended soil, to 13,200μmolkg−1 (87% of the total added) for the shell-amended soil; Ni retention increased from 3767μmolkg−1 (25% of the total added) corresponding to unamended soil, to 11,854μmolkg−1 (77% of the total added) for the shell-amended soil; and finally, Zn retention increased from 4684μmolkg−1 (31% of the total added), for unamended soil, to 14,952μmolkg−1 (98% of the total added) for shell-amended soil. The results of the constant flow transport experiments show that the addition of the 24gkg−1 mussel shells can retain Cu, Cd, Ni and Zn within the first few centimetres of the column length, indicating the usefulness of ground mussel shells to drastically decrease the mobility and availability of these pollutants and to facilitate soil remediation.